delivered the opinion'of the Court.
This suit in аdmiralty was brought by petitioner in the District Court for Western Washington against respondent, the steamship “Pacific Cedar,” and its owner, the respondent Dimon Steamship Corporation, to recover an alleged overpayment of freight and to estаblish a lien on the vessel for the amount of the overpayment. The libel . alleges a contract by petitioner with the owner, by which the latter agreed to receive for loading on the “Pacific Cedar,” on or about January 18, 1930, at named Paсific Coast ports, a quantity of lumber, and to transport it to Philadelphia and New York at the rate of $10.00 per thousand feet, but with a provision that in the event “ a regular intercoastal carrier moves similar cargo at a lower rate,” such lowеr rate should be applied. The libel makes no reference to any bill of lading but sets up that the lumber was shipped and transported, and between March 1st and 20th was delivered, all under the provisions of the contract, and that at the conclusion of the voyage and while the vessel was discharging her cargo, respondent's, at destination, demanded and received payment of freight at the $10.00 rate, although in January, 1930, a regular intercoastal carrier had carried a similar cargo from Seattle to Baltimore at $8.50 per thousand feet.
The lien asserted is for the difference between the freight paid and the freight earned at the agreed lower rate. Upon exceptions the District Court dismissed the libel for want of admiralty jurisdiction. 53 F. (2d) 492.
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The Court of Appeals for the Ninth Circuit reversed the decree dismissing the libel
in personam,
but affirmed so much of it as dismissed the libel
in rem.
61 F. (2d) 187. This Court granted certiorari on petition of the libellant alone,
While there has been a lack of unanimity in the decisions as to the precise limits of the lien in favor of the cargo, see
Osaka Shosen Kaisha
v.
Pacific Export Lumber Co.,
It is not questioned here that thе union of ship and cargo, once established, gives rise to the right of the vessel to a lien on the cargo for the freight money and of the
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cargo on the vessel for failure to carry safely and deliver rightly. .The breach now alleged is only that the freight demanded on discharge of the cargo was in excess of that stipulated by the contract, and respondent insists that the liens in favor of cargo growing out of the contract of affreightment are restricted to those claims founded on breach of the Qbligation to carry and deliver. But the undertaking to charge the agreed freight and no more is an inseparable incident to every contract of affreightment, as essential to it and as properly a subject of admiralty jurisdiction as is the obligation of the cargo to pay freight'when earned, or of the vessel to carry safely. See
Matson Navigation Co.
v.
United States,
It is not denied, and the cases hold, that there is a lien for excessive freight knowingly exacted as a condition of delivery of the cargo,
The John Francis,
In
The Oregon, supra,
the time charterer sold the tonnage of the vessel for a single voyage at á rate in advance оf that stipulated in the charter party. Her captain collected the freight at the agreed higher rate and retained it. The Court of Appeals for the Sixth Circuit, Judge Taft writing the opinion, sustained the jurisdiction
in rem
to recover the excess on the grоund that its collection was incidental to the execution of the maritime contract, and to be treated as an overpayment of freight. This
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conclusion is obviously inconsistent with the view that the affreightment lien in favor of the cargo is dependent on the failure of the vessel to carry and deliver. The right to a lien for the mistaken overpayment of freight was involved in
The Oceano,
It was argued to us, as it has been in other cases, that, as the payment for excess' freight was made under mistake, the demand is upon a cause of action for money had and received, which lies only at common law and not in admiralty. The objection applies with equal force to the liens allowed for еxcess freight, payment of which was procured by fraud or duress, or for freight paid in advance where the voyage was abandoned after the ship was loaded.
2
Admiralty is not concerned with the form of the action, but with its substance. Even under the common law form of action for money had and received there could be no recovery without proof of the breach of the contract involved in demanding the payment, and the basis of recovery there, as in admiralty, is the violation of sоme term of the contract of affreightment, whether by failure to carry or by exaction of freight which the contract did not authorize. See The
Oceano, supra,
132; but cf.
Israel
v.
Moore & McCormack Co.,
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It seems equally obvious that lack of knowledge by the parties at the time of the payment that the freight demanded was excessive should have no bearing on the existence of the lien. There is no hint in the books that the security given by way of lien for the performance of the contract of affreightment depends upon such knowledge. The liability оf the vessel for damage to cargo affords a not infrequent example of a lien which may attach, although at the time of unloading cargo there was no knowledge of the particular events which , effected the breach. See
Rich
v.
Lambert,
Wе see no distinction, either in principle or with respect to the practical operation or convenience of maritime commerce, between, the lien asserted here for overpayment of freight by mistake and those fоr overpayments similarly made but induced by other means. Here, as there, the overpayment, made as the cargo was unloaded, .occurred while the union of ship and cargo continued, and the liability asserted was determined by events contеmporaneous with that union. The circumstances which called the lien into being do-not differ in point of notoriety from those giving rise to other affreightment liens upon the vessel.' While it is true that the maritime lien vis secret, hence is stricti juris and not to be extended by imрlication, this does hot mean that , the right'to the lien is not to be recognized and upheld, when within accepted supporting principles, merely because the circumstances which call for its recognition are unusual or infrequent.
The suggestion made on the argument that the lien asserted here, after the cargo is discharged, is affected by application of the often stated rule that the liens bn ship ■and cargo are mutual and reciprocal, is without basis. It is only the obligations of ship and cargo under'' the contract of affreightment which are to be characterized as mutual and reciprocal, not the liens which result from the
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breach of those obligations. The one lien may come into existence without the other and the lien on the ship in favor of cargo, not being possessory, see
Dupont de Nemours & Co.
v.
Vance,
We note, but do not discuss, the objection that the libel may be taken to allege only a voluntary ovеrpayment of the freight without mistake. We think it may be construed to mean that the payment was made without knowledge at the time that a lower rate controlled. The court below took that to be its meaning. Certiorari was granted to review the question decided below and not the sufficiency of the pleadings to raise it.
Reversed.
Secret liens are not favored, they should not be extended by construction, analogy or inference, or to circumstances where there is ground for serious doubt.
Osaka Shosen Kaisha
v.
Pacific Export Lumber Co.,
Notes
Lien for freight paid in advance but not earned under the terms of the-contract of affreightment:
The Harriman,
See note 1, supra.
The statement that liens of affreightment on ship and cargo are mutuаl and reciprocal is based on the frequently quoted phrase of Cleirac (597): “ Le batel est obligé a la marchandise et la marchandise au batel.” Judge Hough indicated in
The Saturnus,
It has often been pointed out that the lien on cargo is not strictly a privilege (see Pothier, Maritime Contract, Translation by Caleb Cushing, Boston, 1821, 94-50; Hennebicq, Principes de droit Mari
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time, Brussels, 1904, 316) as is the lien on the ship, but is more like the possessory lien of the land carrier and, like it, does not survive the unconditional delivery of the cargo. See
Cutler
v.
Rae,
